deleting apps in reycle bin on PC

I have several devices ipods ipones and ipads..I have several hundred apps for all devices together. I have noticed that when I delete an app off my iphone that i wont be using for a while but i want to be saved in my list of apps on my itunes, I notice i see it in my recycle bin. Now my question is...if i delete it out of my recycle bin do i lose the app or is it that I lose the details in the app by deleteing it off my recycle bin.